In my opinion, the arctic expeditions are easier than the other regions due to the low prices of the polar stations. You have to take in mind that you can buy 3 tickets with only 15 funds, while in the native villages you lose standing and in the missions you have to barter with the priest each time you want to rest. Also, in the polar stations there are not negative events. Because of that I suggest to increase the prices as I mentioned above, so the difficulty would be more balanced.